Updated at 5:09 p.m. after testimony ended for the day. 

A Mesquite police detective testified he believed a fired officer was justified when he shot a man twice in the back, but another expert said the shooting was "unreasonable." 

Derick Wiley, 37, is on trial a second time in the November 2017 shooting that seriously injured 32-year-old Lyndo Jones. 

Wiley is charged with aggravated assault by a public servant. Jurors could not agree on a verdict during the first trial. If convicted, Wiley faces up to life in prison. 

The former officer responded to a 911 call about a suspicious person in a pickup truck parked outside a business. He claimed he thought Jones was burglarizing the vehicle and believed the man may have been armed. 

They were involved in a physical scuffle before Jones started to run away. That’s when Wiley shot the man twice. 

Jones was unarmed. He was sitting inside his own truck when Wiley approached him. 

Lyndo Jones
Lyndo Jones

Det. Brent Ehrenberger was the lead investigator in the case. He testified that body camera and dash camera footage clearly show Jones resisted and evaded arrest, a violation of the law. 

The detective said he doesn't have a problem with the profanity-laced language Wiley used to order Jones out of his truck and onto the ground. 

“Police officers – we cuss,” he said. “Sometimes cuss words can be more persuasive than polite language.”

Ehrenberger said that based on his extensive review of that video it was reasonable for Wiley to assume Jones had a gun.

Defense attorney Kathy Lowthorp questioned the detective about how quickly the Dallas County District Attorney’s Office presented the case to a grand jury. 

Enhrenberger did not file a criminal charge in the shooting, but a grand jury indicted Wiley three weeks after the shooting. 

“From the beginning the DA was very involved? Lowthorp asked. 

“Yes, they were involved,” the detective said. 

He also testified that he believed his “opinion on the reasonableness standard was not taken into consideration.” 

Prosecutors asked how much experience Ehrenberger had investigating police shootings. The detective said Wiley’s case was the first and only officer-involved shooting he has investigated. 

A retired Denver officer who has investigated hundreds of police shootings said Wiley's action was "unreasonable." 

“Based on my background, my training, my experience, the shooting was unreasonable,” said Jonathyn Priest.

He said he reached that conclusion by watching the video and reviewing more than 7,000 documents associated with the case.

Priest was critical of the tactical decisions Wiley made the night he shot Jones. He also criticized the decision by Mesquite detectives to allow Wiley to review the video captured by his body-worn camera and his cruiser’s dash camera before they questioned him about the shooting.

And, Wiley did nothing to de-escalate the situation, Priest said. 

Testimony continues Thursday morning. 

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